Rei Kurosaki is a “colorless” in a world where one’s worth is defined by the color of their mana. With no magical skill of his own, he spends years as nothing more than a porter for his talented but arrogant younger brother Kai. That is, until a raid against Chronos, the God of Time and Space, wipes out his entire party. On the brink of death, Rei awakens a hidden skill that allows him to steal skills and rewind time itself. Sent back to the past, Rei begins again with knowledge of what is to come and a power no one else possesses. As Rei levels up at an unprecedented rate, he must prepare for the eventual return of Chronos while dealing with those who once treated him like trash. (Source: WEBTOON)

In a world where upon turning 18, individuals are granted a "class" by the gods. The presence or absence of "skills" within the class surpasses any efforts and determines one's entire future. In this unequal world, Reit, who has trained to become a holy knight, is mercilessly given the class of during the classification process. He is then banished from the city by his father, the Duke. Struggling to make ends meet as a porter, one day, a merchant caravan is attacked by bandits. Though he fights to save a child, realizing he cannot match the combat skills of the enemy, Reit prepares for death. However, in the moment he lands a punch on one of the bandits as a last act of resistance, a mysterious voice resonates in his head...

In a once-in-a-lifetime "Aptitude Ceremony," the protagonist, Alto, receives the lowest possible magic aptitude and is branded useless, leading to his expulsion from the Wellsley family. His dream of becoming a knight shattered, Alto sinks into despair and spends his days being overworked for meager wages. However, encouraged by his childhood friend who shares his dreams, Alto's unique skill, "Automatic Magic," awakens! Thanks to this skill, he gains experience points anytime, anywhere! Alto grows with super efficiency, surpassing his lack of talent!! But then, he gets expelled from the adventurer's guild too -- !?